The present invention relates broadly to apparatus for disposing of waste aerosol cans. More specifically, the present invention relates to a system for safely evacuating and crushing spent aerosol cans, and disposing of their unwanted waste contents in an environmentally sound manner.
Aerosol cans typically comprise an interior, pressurized chamber protected by a rigid exterior sleeve. The pressurized chamber is normally filled with a liquid product such as hair lacquer and subsequently sealed by a spray valve. A gaseous propellant such as chlorinated hydrocarbons, butane, vinyl chloride, or nitrogen gas is forced into the pressurized chamber which is thereafter sealed. Such cans often contain dangerous or toxic substances. Because they are packaged under such high pressure, disposal by incineration is unsafe because of the danger of explosion.
In recent years, public awareness as to the environmental and human health risks of uncontrolled waste disposal has greatly increased. In response, various organizations including the Environmental Protection Agency (EPA) have undertaken to study the toxic effects of various compounds, and set forth guidelines for controlling disposal of such compounds. Certain materials have been classified as hazardous and may not be applied to the land in any form, whether diluted or treated. In the past, partially empty aerosol cans were disposed of in conventional 55-gallon drums. As of May, 1990 aerosol cans known to contain EPA-listed chemicals may no longer be disposed of in landfills. Aerosol cans may not be landfilled unless proven empty, and delivered in suitable storage containers.
Moreover, disposal of whole aerosol cans is impractical from an economic standpoint. Roughly 200 unevacuated cans could be fitted into a typical drum. Routinely, the cost of disposing of a 55-gallon drum of aerosol cans as solid waste runs roughly $1000.00. Hence, disposal of the cans involved is too expensive to serve the economic interests of industry.
Thus, landfill disposal of aerosol cans as solid waste is not only environmentally unsound, but also economically questionable.
On the other hand, a 55-gallon barrel of toxic liquid waste can be incinerated at a price roughly $150.00. Based on my experimentation, a 55-gallon barrel will contain the fluid contents of roughly 5000 aerosol cans. Once the cans are emptied, they can be crushed or comminuted for recycling. Thus it is desirable to provide apparatus for evacuating aerosol cans and crushing them to ensure environmentally sound disposal.
In the prior art known to me, various methods have been proposed for evacuating aerosol cans. For example, Cound, in U.S. Pat. No. 4,459,906, issued Jul. 17, 1984 describes a hydraulic can crusher that mechanically feeds a can into a crushing compartment, punctures the can with a rigid lance associated with an air chamber, and collects the released products into a processing tank. The system employs hydraulics for powering the aerosol can crusher.
Various prior art patents specifically directed to the safe evacuation and disposal of aerosol products include U.S. Pat. Nos. 3,935,973 and 3,935,974, issued Feb. 3, 1976 to Weyn; and Feldt Pat. No. 4,407,341, issued Oct. 4, 1983. The latter device employs a discharge ram, a suction chamber for receiving gaseous products, and a liquid container for receiving the liquid component for processing prior to disposal. Large-scale can compressors are illustrated in U.S. Pat. No. 4,474,108 issued to Lonze on Oct. 2, 1984 and Heiser, U.S. Pat. No. 3,916,780, issued Nov. 4, 1975.
Additionally, Chipman Pat. No. 4,349,054 issued Sept. 14, 1982 mechanically engages an aerosol can within a chamber. The can is punctured with a rigid, vented ram associated with an isolation chamber. Flammable propellant products are captured in the container for processing. The chamber feeds escaping gases and liquid product into a filtering device prior to venting.
One very relevant prior art system is taught by Meadows, U.S. Pat. No. 4,356,981, issued Nov. 2, 1982. This system mechanically punctures the can, separates the gaseous from the liquid component, heat-processes the liquid component below atmospheric pressure, and vents gasses resulting from processing into the atmosphere via a venturi.
However, the aforedescribed systems are generally too complex and expensive for use by individuals such as in a typical waste recycling center. As public awareness of the environmental and health hazards increases, the demand grows for safe, practical means of managing such solid waste disposal. Unfortunately, none of the prior art can crusher systems known to me is capable of conveniently and safely containing, evacuating, and crushing an aerosol can in a single cycle.